Combined Servodrive Unit Adds Flexibility to Packaging Machinery

Packaging developments and changes in consumer demands continue to fuel the need for product diversity. Therefore, packaging machinery OEMs constantly seek ways to improve their machines to handle rapid product changeover. Today, the most significant purchasing criterion for a packaging machine is usually its flexibility. It’s through shorter changeover times that the end packager can economically meet the packaging requirements of modern consumer products.

Modular machine concepts help meet these needs. That’s why KHS AG has used servo and control technology from Rexroth since the mid 1980s. KHS has used innovative developments like modular dry area solutions and labeling technology, and today, is incorporating decentralized servo drive technology in modular machine construction.

The flat mounting of the control electronics on the Rexroth IndraDrive Mi combined servo drive help reduce the unit’s size by 30% over other servo-drive designs.

KHS AG, with headquarters in Dortmund, Germany, is a leading provider of filling and packaging technology in the beverage industry worldwide. Several years ago, management developed a comprehensive, modular machine program that focuses on using combinable mechatronics modules to flexibly and economically meet its customers’ growing needs for versatile packaging machinery.

The next development step is the implementation of decentralized servo drive technology. For this, KHS recently began using Rexroth’s compact IndraDrive Mi integrated motor and drive. The unit combines a traditional servomotor and control into a compact unit. The motor housing surface serves as a heat sink for the control electronics, which are mounted in an ultra-flat fashion on top of the motor. This design makes the unit 30% smaller than servo drive units that put the electronics behind the motor. In addition, the IndraDrive Mi is more than 50% smaller than traditional servo drives that use a separate motor and converter, shrinking cabinet space requirements.

The unit’s design also reduces cable connections. Only one cable is needed for both power supply and communication through the Sercos interface. Up to 20 IndraDrive Mi units can be connected together without additional distribution boxes or modifications in the cabinet. More than one string of drives can be connected in parallel to a single supply unit.

By connecting multiple units in sequence, the number of required cable connections is further reduced. Drives can be added flexibly as needed, without requiring any changes to the control cabinet. The control cabinet volume can be decreased by up to 70%, while cabling needs cut by up to 85%.

The servo drive unit combines high power density with full function. As a power supply, Rexroth IndraDrive C converters or IndraDrive M supply units can be used – and the whole system combined smoothly with converters and inverters from the IndraDrive platform. These servo drives are equipped with over a hundred technical functions, including the integrated Motion Logic according to IEC 61131-3.

Only one cable is needed to supply power and communications to all drives.

KHS built a shrink packager in its Innopack Kisters SP series – in this case, for packaging wine bottles. The SP series handle the manufacture of foil multi-packs out of sturdy individual products. Along with the Innopack Kisters SP shrink packers, the series provides power range from 35 to 150 cycles per minute in continuous operation. These machines package cans, jars and bottles as well as pre-packaged products in the beer, soft-drink, hygiene, food and non-food industries.

Additionally, these machines economically create multi-packs with clear, scatter-printed or pinpoint-printed foil. Packaging costs remain low because shrink foil is used as the only packaging material. The drive is controlled using Rexroth Motion Logic for one- to three-row processing, where the speed automatically adjusts to match the actual line capacity. An integrated, user-friendly error diagnostic system keeps downtime to a minimum.

Through the use of a small, yet powerful servo drive system, engineers at KHS have the flexibility to design packaging systems, like this Innopack Kisters SP shrink packer, to meet customers changing demands.

With the IndraDrive Mi, KHS can easily combine different machine modules according to customer demands. For example, with the addition of two extra machine modules, a shrink packer can become a tray shrink packer. Two more IndraDrive Mi drives are simply added to the existing seven. In the control cabinet, as well as in the total wiring of the system, practically nothing changes.“With the use of IndraDrive Mi, the system costs are significantly reduced, especially in the required installation effort for the control cabinet and wiring,” says Dirk Langanki, manager of electrical construction and development at the KHS Competence Center for Packaging Technology.

At KHS, the technology has proven itself through extensive testing. The packaging specialist has delivered its first IndraDrive Mi equipped machine to an end customer in the beverage industry. The machine was so successful that KHS plans to build more machines with the new IndraDrive Mi.

Bosch Rexroth
www.boschrexroth-us.com

KHS
www.khs.de

: Design World :